The likely by-election that looms thanks to the SNP MP Margaret Ferrier facing suspension from the House of Commons over Covid-breaching shenanigans will be rather instructive when it comes to the biggest, and still most undiscussed, issue in Scottish politics: where are left-wing voters heading?

Will the progressives the SNP captured from Labour stay with nationalists now or shift back to their old home?

There’s many conflicting factors at play here. Firstly, the SNP wounded itself in the eyes of many progressive voters during the recent lunacy of the leadership contest. Yes, the progressive candidate won, but many left-wingers who have backed the SNP won’t feel easy about what the contest revealed about nationalists.

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Nearly half of SNP members who could be bothered voting backed the socially and financially conservative Kate Forbes. So it’s pretty hard for the SNP to pass itself off as a party that’s left of centre in its soul anymore.

Behind the progressive Humza Yousaf, there are a lot of people who leftie-liberal types would feel pretty uncomfortable sharing a party with, that’s an unavoidable truth.

So at first glance, it seems possible there will be quite a lot of left-wing voter flight. However, where will those voters go? If you’re a lefty who parted company with Labour and then voted Yes in 2014 is the Blairism of Keir Starmer really an attractive prospect? Perhaps not.

However, many left-wing voters may use another equation to make a call. In their eyes, the Tory government in Westminster is an abomination. They want it gone at all costs. What’s the best way to achieve that? Via the SNP or via Labour?

Evidently, anyone with a brain in their head can see that independence is off the table for quite some time. So voting SNP - an SNP now smeared with the ‘Tartan Tory’ brush - isn’t guaranteed to get rid of the Conservative government, anymore than it’s guaranteed to lead to indyref2. Many progressives will worry if by voting SNP - a party they no longer feel much sympathy for - they may unwittingly allow the Tories to squeak in at the next election.

Yet, the positioning of Labour may still be just too toxic for the left. Many will find it hard to forget recent statements by John McTernan, Tony Blair’s former political adviser, that “Thatcherites are safe to come home to the Labour Party” thanks to Starmer.

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